Have you uplugged the printer (not just turned it off)? Run the printhead under hot water until no more ink comes out, dry it, and re-install it while the plug is out. With the lid up, plug the printer back in, and press the power button five times ...
Jason used ethanol (you can get "denatured" alcohol from a hardware store); I used isopropanol (rubbing alcohol). Both should work about the same. Set the print head, jets down, on several thicknesses of paper towel. With an eyedropper or with a Q-ti...
Same issue with an MX-700 - inks went dry, no warnings. I think the ink leaked out, since the black cart was relatively new. There is no "contact us" link, so whoever is posting that advice (if it is a person at all) might be wondering why business...
Cleaned the head thoroughly with hot water and then isopropanol (rubbing alcohol). Dissolves the inks nicely, so it presumably works as well as ethanol. Re-installed print head and inks - and now I have an Error Code 5200. Machine won't even power ...